Crime Slain California Teacher Seemingly Begs for Her Life in Suspected Killer's Accidental Voicemail Jill Thomas Grant's body was found on a golf course in 2013 By Steve Helling Published on February 22, 2017 12:26 PM Share Tweet Pin Email Trending Videos Photo: Facebook A California math teacher killed in 2013 may have been recorded begging for her life in an accidental phone call placed by her alleged killer, according to court documents obtained by PEOPLE. Jill Thomas Grant was found dead on a golf course in December 2013. The 41-year-old’s throat had been slit with a box cutter and she had been run over by a car. Prosecutors have charged her boyfriend, Michael John Franco, with her murder. On the night Grant died, the couple was throwing a party at their home in a gated community. Party guests arrived, but couldn’t make it past the gate. Franco allegedly cancelled the party, which prompted Grant’s brother to call police. According to the court documents filed last week, prosecutors now have a voicemail that possibly recorded Grant’s last words. The night of the killing, a friend received a voicemail from Franco’s phone. The call appears to be an accidental dial. Prosecutors allege that the recording captures Grant bargaining for her life, trying to convince Franco that they could call 911 and say that someone else had attacked her. • Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter. The documents allege that most of the recording is inaudible, but that Grant can be heard saying, “What if I drive the car someplace and call myself and say I was attacked? Would that work?” Indio Police Department Additional Evidence Prosecutors believe that the recording bolsters an already-strong case against Franco. According to a case summary obtained by PEOPLE, prosecutors allege that bank security footage shows him using her ATM card the night she was killed. They also allege that, upon his arrest, Franco told authorities, “I’m going to prison for the rest of my life.” Prosecutors allege that he confessed the murder to his cell mates, and that they will be called to his trial as witnesses. • Pick up PEOPLE’s special edition True Crime Stories: Cases That Shocked America, on sale now, for the latest on Casey Anthony, JonBenét Ramsey and more. Additionally, prosecutors allege Franco was arrested driving Grant’s car. According to the documents, police found blood on the front bumper and grass in a wheel well that appeared to come from a golf course. But Franco maintains his innocence and has pleaded not guilty. His attorney has argued that portions of his confession to cell mates should be excluded. He is being held without bond and a trial date is expected in the spring. Franco’s attorney did not immediately return PEOPLE’s call for comment.